docs: def get_form(self, request, obj=None, **kwargs):
          """
          Add the default alternative dropdown with appropriate choices
          """
          if obj:
              if obj.alternatives:
                  choices = [(alternative, alternative) for alternative in obj.alternatives.keys()]
              else:
                  choices = [(conf.CONTROL_GROUP, conf.CONTROL_GROUP)]
  
              class ExperimentModelForm(forms.ModelForm):
                  default_alternative = forms.ChoiceField(choices=choices,
                                                          initial=obj.default_alternative,
                                                          required=False)
              kwargs['form'] = ExperimentModelForm
          return super(ExperimentAdmin, self).get_form(request, obj=obj, **kwargs)